Each year, a number of countries across the globe face the devastating effect caused by forest fires or wild fires. Forest fires cause huge economic losses by damaging valuable property as well as other valuable resources. In addition, huge sums of money are spent each year on fire fighting and evacuation of people to safe places. In the USA for example, during the month of October 2007 an area of 2090 square kilometers in southern California was burnt by wild fires and over $1 billion was spent on fire suppression. More than 340,000 homes in the stretch from San Diego to Los Angeles were evacuated and about half a million people were affected. Forest fires also have a devastating effect on the environment. A large quantity of carbon-dioxide and other noxious gases that are emitted during forest fires cause pollution and contribute to the green-house effect leading to global warming. It has been observed that restoration of the ecosystem in the area devastated by forest fire especially those closer to urban areas is difficult leading to further shrinkage of woodlands.
The effect of a forest fire is often wide spread and not limited to the physical boundaries of the forest fire. By way of example, some years ago the forest fires in Indonesia blanketed the whole of Singapore with smoke for many days disrupting normal life and forced people to wear breathing masks outdoors.
Over the years, the frequency and the extent of wild fires have increased. Some major factors that contribute to this increase are various human activities. As encroachment of wild land increases, the risk of wild fires in areas that were earlier considered to be safe has also increased.
Forest fires are generally caused by rise in temperature as well as low moisture levels in the atmosphere and in the soil during summer and dry seasons. The fires quickly spread to large areas often on account of winds.
Conventionally, forest fires or wild fires are controlled by prescribed burning of designated forest areas. But prescribed fires are controversial and are opposed by private land owners and timber businesses. It is also not possible to use this method in areas that are near human habitat. In addition, at times it may become difficult to control the extent of such fires and, prescribed fires are not always practical and effective solutions to control forest fires.
Some available systems to extinguish fires use temperature sensors that indicate fires, which in turn activate sprinklers around houses that extinguish the fire. However, these systems only provide protection against small local fires and are not useful in fighting large fires often advancing rapidly due to high winds. Moreover, most of these systems use municipal water from urban water supply systems making them uneconomical to use for fighting fire on a large scale. Most of these consider only the temperature aspect, but other environmental aspects also need to be taken into account. Moreover, such systems do not attempt to prevent the fire, but rather focus on putting out or containing the fire.
Therefore, there is a need to develop a wildfire prevention system that is economical and effective against large wild fires and takes into consideration all relevant environmental factors responsible for wildfires.